Rotary pump



Get, 14, 1930. O E EN ET AL 1,778,169

ROTARY PUMP Filed March 7. i928 /NVEN7'0RS:

V MWM W V Patented. Oct. 14, 1930 UNITED STATES PATENT OFFICE ROTARY PUMP Application filed March 7, 1928, Serial No.

When a rotary pm. p 1S employed for exhausting the air from siphonic conduits or from the suction pipes of pumping plants and the like, it is usual to provide a. valve in 5- the piping leading from or to the exhauster pump so that said piping can be closed in order to render the pump inactive as soon as it begins to draw liquid. This valve is operated by hand and must be constantly attended to, since the services of the pump may at any time be required.

The object of the present invention is to obviate the necessity of attending to the valve, and the invention consists in the combination with a rotary pump of the kind operating by means of a circulating liquid, of

means whereby a stop cock is automatically opened and closed under the influence of the pressure variations in the pump due to the absence or presence therein of air.

To obtain thisresult, the cock is controlled by a lever and by a piston arranged in a cylinder which communicates with the pump caslng. The invention is illustrated in the accompanying drawing which represents a sect-ional View of the arrangement.

The cylindrical pump casing a contains an eccentrically disposed, vaned wheel by the rotation of which and by means of an auxiliary liquid which circulates along the circumference of the casing air or liquid is sucked in through a port It and discharged through a port 2'. The pump is connected through the port h which the si honic conduit or other element which is to kept clear of air In the arrangement shown, a stop cock b is arranged in the pressure pipe of the pump, and the plug is connected y a lever arm and a link to a piston d arranged in a cylinder 0. The latter communicates through an aperture 0 with the pump casing a, said aperture being situated in the side of the casing below the rotor and sufiiciently near the latter to be swept by the vanes, i. e., in the region where the air, if present, will be maintained by the auxiliary liquid. The ston carries a weight g and may in additlon be controlled y a p n cockplug so as to retain the latter normally 7 actmg on the leverarm of the 259,798, and in Germany June 22, 1927.

in open position. The port 2' is comparatively small, however, and as soon as the pump begins to draw liquid, the port is incapable of discharging the latter at the same rate as that at which it is impelled by the rotor. Thus the pressure in the casing a will be suddenly increased, and the increased pressure will be communicated through the porte to the cylinder 0 for raising the piston?) and closing the valve. As long as the water pressure persists, the valve remains closed, but as soon as air enters the induction pipe, the water in the cells between the vanes flows back through the port it into the induction pipe and relieves the excessive pressure in the casing. The valve will then be reopened, and the air will be pumped out of the system.

The cock may be arranged at the suction side of the pump in which case, however, it is adapted to effect only an incomplete closure so that smaller quantities of air, admitted through leakage or the like, may be continually pumped through without any substantial discharge of liquid. For this purpose the cock plug may be provided with a small duct which opens when the normal, plug aperture is closed.

We claim:

1. A rotary pump comprising a casing, a vaned wheel arranged eccentrically within the casing and sweeping theend walls andthe top part of the circumference thereof, said casing having induction and exhaust ports. situated in the end wall at opposite sides of the wheel axis and at the base of the vanes, the exhaust port being smaller than the induction port, a pipe communicating with the exhaust port, a valve in said pipe, an hydraulic controlling device for said valve tending to maintain the valve open, and a pipe connecting the controlling device with the pump casing through a port situated in the end wall of the casing below the wheel axis so as to be swept by the tips of the vanes, the controlling device being adapted to close the valve on an increase of pressure in the casing.

2. A device as claimed in claim 1 wherein the valve controlling device consists of a spring-controlled piston and a cylinder .for said piston. I

3. A device as claimed in claim 1 wherein the valve consists of a. cock plug and the controlling device, of a piston, a cylinder for said piston and a lever arm mounted on the plug and linked to said piston.

OTTO SIEMEN. J OHANN ES HINSCH. 

